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Fanless AC

Cooled water sprayer conditioning.
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(+2, -1)
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The heat from the vapor-compression refrigeration system is used to evaporate water, which preliminarily cools the coolant water, which is then further cooled through refrigeration.

The now cold coolant water is sprayed thinly into the room onto the ceiling where it is gathered as it condenses, and taken to the side of the room. No fans, just an internal cloudy ceiling with no rain. For a hot day. The walls have passive dew condensers so the room is basically dry, giving the good natural feeling of outdoors.

A few plants with LED lights complete the feeling giving off oxygen and a nice fragrance.

== Adendum from the annotations ==

Its almost frozen water being sprayed on the ceiling. I'm not looking for energy savings by an evaporator, I'm using regular refrigeration with gas compression. The evaporator is in the outside unit, and its just a preliminary step.

But the FAC device is not cooling the air, instead its almost freezing water. and the frozen liquid droplets of water are what are sent by spray to cool the room.

Passive liquid gathering and passive humidity extinguishers are not that expensive and work pretty well. No need for fans.

pashute, May 23 2022

Wet bulb temperature https://www.science...et-bulb-temperature
[doctorremulac3, May 23 2022]

Dewpoint and relative humidity http://cimss.ssec.w...xwise/rh/page2.html
[doctorremulac3, May 23 2022]

Instachill https://www.mitre10...v2-85w-10l/p/366253
Also, insta-damp... [neutrinos_shadow, May 23 2022]

[link]






       Humidity.
doctorremulac3, May 23 2022
  

       //is gathered as it condenses, and taken to the side of the room//   

       How, without fans?
Voice, May 23 2022
  

       You're essentially attempting cooling with water evaporation. This will lead to close to 100% humidity. This will feel horrible and turn your house into a mold farm. It will also not be air CONDITIONING. The conditioning part, rather than just cooling is the management of humidity. Dropping both the temperature and humidity are synergistic features.
bs0u0155, May 23 2022
  

       These are known as swamp coolers.
RayfordSteele, May 23 2022
  

       There are ads on TV here (New Zealand) for evaporative coolers (linky). They're rubbish, of course. Effectively "here, make your home damp!". Might work OK in a desert climate, but not down here. Should be illegal to sell them here (damp, badly insulated houses are a social health problem here).
neutrinos_shadow, May 23 2022
  

       //evaporative coolers//   

       They work quite well in Western Australia (which is, yes, quite deserty), and I imagine they work quite well in Israel, too, which is, I think, where [pashute] lives.
pertinax, May 24 2022
  

       hmmmm...   

       there is a way to wet a clay jar and place a wet towel over it so that the inside of the jar stays at two or three degrees if kept in the shade and the cloth stays damp.
There should be a way to control how much moisture is absorbed by the clay compared to the amount of coldth output by the descending air.
  

       Still gonna need a fan to blow it around though.
Maybe solar powered...
  

       I'm wondering if I can use an evaporative cooler to boost the AC in my bedroom? Having a 3 floor house with insane whole-house HVAC means that the bedrooms stay warm while the basement gets all the cool air. Don't get me started on how airflow is essentially managed with ill- fitting doors.   

       Anyhow, if I put an evaporative cooler at the far side of the bedroom it should lower the temperature at the cost of increased humidity, but, that should just be removed by the AC unit, so I'm just moving extra heat energy through a water vapor cycle, it's not magic. But, will the extra humidity offset the temperature benefit?
bs0u0155, May 24 2022
  

       If your central A/C is effective enough to remove that additional moisture in the room you put the evap cooler in, it would be effective enough to just cool the room without the evap cooler.   

       In other words you're just putting additional load on your A/C system. And you might create a cooler temperature area with high humidity that'll feel much warmer than it is. Comfort is a temperature/humidity thing.   

       You can look up climate zones where evaporative coolers are useable but rule of thumb is the more like a desert the better. A simpler rule of thumb is they suck.
doctorremulac3, May 24 2022
  

       //if I put an evaporative cooler at the far side of the bedroom it should lower the temperature at the cost of increased humidity, but, that should just be removed by the AC unit, so I'm just moving extra heat energy through a water vapor cycle, it's not magic. But, will the extra humidity offset the temperature benefit?///   

       So a swamp cooler with no hot air out? Not worth it. But swamp coolers in general are great for what they do.
Voice, May 25 2022
  

       If you're in the right climate zone.
doctorremulac3, May 25 2022
  

       //it would be effective enough to just cool the room without the evap cooler.//   

       The problem is that it's whole-house HVAC. The system is perfectly capable of cooling the house ON AVERAGE. The problem is the bedroom is at the top. The basement gets the coolest air, then the ground floor and the bedroom will inevitably be hotter. Then the bedroom is specifically heated, primarily by my unusually high thermal output, and the sun hitting the bedroom wall/roof pretty much straight from dawn.   

       If it were my house, I'd ritually sacrifice the whole-house unit and all it's stupid great ducts and noise with a 30mm cannon. Throw a good mini-split in the bedroom. I don't know who thought the minimum unit of heating and cooling should be EVERYWHERE all the time. But they need ritually sacrificing with something slower than a 30mm cannon.   

       It's a STAGGERINGLY inefficient system. There's about 7-8 HVAC outlets and only 2 intake/returns. So there's air going into some rooms but having no path back. The solution, and this makes my UK friends laugh, is to just cut the door so that there's a 1-1.5" gap under it. Of course that means that the outlet pressurizes the room slightly, and pushes the COLDEST air out under one door, under a second door and up into the return/intake. Of course it blows all the dust into the rooms with the return as a nice by product.   

       What I'm going to do, is ignore the rules on window AC units. Then see if I can borrow a ladder. I have a couple of spare diaphragm pumps and some tubing. A few gallons of water sprayed over that portion of the roof through the night/morning should have a powerful cooling effect.   

       I also noticed that my window AC unit deliberately pools the condensation water in the condenser section and sort of allows the fan to splash it around the place. It will be more efficient that way, but I think I can further enhance it, a small pump drawing from the (now blocked) drain port that recirculates and drips evenly over the condenser fins should work better. Even better still if I can work in a way of slowly metering in some of the not-stolen at all industrial alcohol. Keeping it at ~10% or so should be more efficient and super safe.   

       Anyway, the point about the evaporative cooler being that I'm trying to specifically cool the hottest room in the house. The HVAC IS effective enough, it's just that to get the bedroom to a sensible temperature, I'm spending money cooling all the parts of the house I'm not in to an unreasonable degree.
bs0u0155, May 25 2022
  

       Couple of things:   

       Assuming the A/C is properly sized, you need to air balance the system.   

       First off establish your flow paths from the diffusers (outlets) to the returns. Slots under the doors are better than nothing, but you can also put slotted panels in the walls or doors. This might effect soundproofing of the bedrooms so just don't have loud sex. You might have to stop having marital relations all together, they teach you this on day one in HVAC school. (not that I've ever been to HVAC school, but I assume they go over that in the introductions)   

       Then get yourself a anemometer to measure your airflows through the various supply vents. If you don't want to do that, dhunno, maybe you can just tie a ribbon to the various outlets and look at the angle of their fluttering. Bigger rooms need more fluttering, smaller less. Just thought of that so don't know if that would work but better than nothing I suppose.   

       The further from the unit the vent is the more static pressure it has to overcome, that's just the resistance to airflow through the ducts. Close up the vents closer to the unit and open up the ones further till you get reasonably balanced air flow through all of them.   

       Consider upping your insulation, attic first, some nice R-30 batt insulation instead of blow in or wimpy R-11. Then if you're really rich put in double glazing, that's a big deal and you can justify it by lowering your energy bills. Probably get some breaks from the city too for upping the energy efficiency of your home.   

       Used to design this stuff when I was a teenager. Don't know how much of the environment I've saved by designing more energy efficient houses but it probably added up over the years. I don't like to use the word hero, but hey. If the word fits, who am I do disagree?
doctorremulac3, May 25 2022
  

       And by the way, goes without saying just close up the vents to the rooms you're not using. Don't want to stagnate your air flow too much and freeze up your evaporator coils but sounds like that's probably the least of your worries. Point is an un air-balanced system is basically just a noise maker.
doctorremulac3, May 25 2022
  

       Clearly what's needed is distribution of liquid nitrogen throughout the house.
Voice, May 26 2022
  

       Liquid helium would be better.
doctorremulac3, May 26 2022
  

       Agree with everything doc said. And tape up your duct joints.   

       I run just the hvac fan all night to move the cold air from the basement to the rest of the house and it does a great job freezing us out by morning, to where I have to turn the system to heat and set the heat to a minimum point.
RayfordSteele, May 26 2022
  

       Its almost frozen water being sprayed on the ceiling. I'm not looking for energy savings by an evaporator, I'm using regular refrigeration with gas compression. The evaporator is in the outside unit, and its just a preliminary step.   

       But the FAC device is not cooling the air, instead its almost freezing water. and the frozen liquid droplets of water are what are sent by spray to cool the room.   

       Passive liquid gathering and passive humidity extinguishers are not that expensive and work pretty well. No need for fans.
pashute, May 26 2022
  

       //And tape up your duct joints.//   

       Yes. And while you're up there wrap them in insulation as well if they're not already.   

       Pash, nobody likes outside the box ideas more than me, but I've spend enough years in my youth working with humidity extinguishers to know that's a much cooler name for what they currently call dehumidifiers.   

       Bunning this for that alone. [+]
doctorremulac3, May 26 2022
  

       //Close up the vents closer to the unit//   

       I was reluctant to do this, since we had coil-freezing problems in the past. But I'll give it a try. I can definitely close off 2 bathroom vents at night, since the bathrooms are in the corners they're particularly warm... closing the bathroom doors effectively turns the rooms into insulation.   

       Ultimately, and irritatingly, the house is not mine. If it was, man I have ideas. Houses follow the basic rule that: the more important it is, the worse we are at it. They basically don't change, and often, when they do it's for the worse.   

       At the very least I'd have an air handling system, filtered intake that keeps the house at mild positive pressure with a heat exchanged exhaust. That way, you actually get some air exchange in a managed way, not just whatever leaks the drier is pulling air through.   

       Still, there's something deeply odd about our row home, it requires ludicrous amounts of cooling, yet heating is totally unnecessary until we get sustained temps below 30F. I've been in both neighbors houses and it's not like they're maintaining 93F. I've checked the adjoining walls with an IR thermometer, it's not remarkable. The house just is warm, best current hypothesis is that we're on a very small volcano.
bs0u0155, May 26 2022
  

       //Close up the vents closer to the unit//   

       //I was reluctant to do this, since we had coil- freezing problems in the past//   

       Yea, just hire a contractor with the proper tools to air balance the system. I didn't just tweak a vent here and a vent there, I got all the numbers, ran the calculations and knew how much CFM should be coming out of each point and adjusted them accordingly.   

       //Still, there's something deeply odd about our row home, it requires ludicrous amounts of cooling, yet heating is totally unnecessary until we get sustained temps below 30F. //   

       Guessing you're slab on grade. That's a big passive thermal storage element. So if you're hot during the day, that slab retains the heat and radiates it back at night.   

       But I'd just hire a contractor to come out and evaluate your system. I can do it for... one million dollars.   

       I'd shop around though.
doctorremulac3, May 26 2022
  

       //Guessing you're slab on grade.//   

       Oh no. Amateurish thin concrete poured onto dirt in the basement. And I'm talking about the winter. The house can go weeks in the 30's F range and not need heat. It's my current biggest mystery along with how plastic bags spontaneously inflate in freezers.
bs0u0155, May 26 2022
  

       Yea, that's slab on grade. Just a fancy name for concrete on dirt.   

       Easier to charge more with the name that people don't understand. Can get more for "We survey and laser level the construction envelope footprint, excavate, rebar and pour the slab, level and build up the stemwall…" than "We dig a hole and pour some shit in it."
doctorremulac3, May 26 2022
  

       heh, so If i disconnect the AC ducts, allow it to run in the basement sucking heat out of the earth and move the condenser into the dining room, I can have a DIY redneck ground source heat pump like them fancy Scandiwegians?
bs0u0155, May 26 2022
  

       I'm going to say... yes, just because I'm curious to see what happens.
doctorremulac3, May 26 2022
  
      
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